Patent Document 1 discloses an X-ray image sensor which outputs an X-ray image of an intraoral site or the like as an electric signal. This X-ray image sensor comprises an X-ray fluorescent screen, a CCD sensor, a container accommodating them, and the like. A conductive member such as an aluminum foil or the like surrounding the X-ray fluorescent screen, CCD sensor, and the like is disposed within the container and electrically grounded. The conductive member is connected to a shielding wire within a signal cable connected to the CCD sensor or the like.    Patent Document 1: Japanese Patent Application Laid-Open No. 7-280944